Examples of Fischer-Tropsch synthesis processes steps to prepare said Fischer-Tropsch product and hydroisomerization steps (a) are known from the so-called commercial Sasol process, the commercial Shell Middle Distillate Process or the non-commercial Exxon process. These and other processes are for example described in more detail in EP-A-776959, EP-A-668342, U.S. Pat. No. 4,943,672, U.S. Pat. No. 5,059,299, WO-A-9934917, AU-A-698392 and WO-A-9920720.